Good Morning brother Carl,
Most of the time pictures are worth thousands of words so I included a few here just in case someone wanted to duplicate .
The bearings are a rear axle from a front wheel drive vehicle ( a mini van I think ) . Years ago when building my sawmill ( 96-98 or somewhere in that time span ) I robbed a couple of these axles off of junk. I have used this axle housing for the idler wheel that the band blade runs on . It has a lot of tension on it but has had no problem. This bearing is a spare that I had forgotten I had.
The application were I need the 1000 rpm pto are all light work and don’t foresee a problem with the bearings. However if there is a failure it may be from the light pto shaft that I used . It is and adapter 1 1/8 inch 6 spline to a 1 3/8 inch 6 spline with the base of it hollow. If it does fail I have some solid shafts I can weld on .
I was able to put this together and only add 3 inches to the pto shaft compared to the other shaft.
I once had a fordson major with a 1000 rpm pto and used this procedure ( visa versa ) to reduce the speed to 540 . I ran it pulling heavy machines like my Heston hay roller and hay mower until the tractor played out a few years ago but the gear reduction unit is still well…
Edit … The short axle does have two sets of roller bearing , an inter and outer .